This invention relates to the catalytic hydrodealkylation of alkylaromatic compounds to produce a product containing benzene, toluene, and xylene.
Hydrodealkylation (HDA) has been used to convert alkylaromatics to BTX (benzene, toluene, and xylene). Benzene is an especially desired product because of its high demand. Conversely, C.sub.9 + aromatics have relatively low value as compared with benzene.
Thermal HDA has been used to convert C.sub.7 /C.sub.8 alkylaromatics to benzene, and remains as an important technology for benzene production in many developing countries. Some studies have indicated that the conventional thermal HDA process can be modified so as to use a C.sub.9 + feedstock (see Oil and Gas Journal, Mar. 20, 1989, pp. 91 to 99).
U.S. Pat. No. 4,341,662 discloses BTX production from heavy reformate in substantially the portion in said reformate of single ring aromatics bearing none, one, or two methyl groups by contacting the heavy reformate at 800.degree.-1000.degree. F. with a zeolite of low acid activity.
A process has been developed for catalytic HDA which can produce benzene and BTX from feedstock containing C.sub.9 + aromatics, such as, for example, a heavy aromatics plant stream or high boiling point gasoline.